The purpose of this project is to develop and distribute a concise software system for the analysis of positron emission tomography (PET) images, with special attention to the generation of functional images. The system's structured design will facilitate use for both research and routine data analysis and image display. The system will enable researchers to create analysis and imaging protocols with strong support from the analysis system. The protocols may be used for routine analysis through a simple, user-friendly interface. System functionality will include PET image display, region of interest (ROI) definition, extraction of time-activity curves (TACs) from ROIs in a set of sequential, time-binned images, analysis of TACs using mathematical models, and functional image generation and display.